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This chapter gives a general description of 1-Mbit flash memory.
There are three ways of programming and erasing to and from flash memory as follows:
1. Programming and erasing using parallel writer (Minato Electronics MODEL1890A)
2. Programming and erasing using serial writer (Yokogawa Digital Computer AF-200)
3. Programming and erasing by executing program
This chapter describes "3. Programming and erasing by executing program".
25.1 Overview of 1-Mbit Flash Memory
1-Mbit flash memory is placed in the FE to FF banks on the CPU memory map. As with mask ROM, the
function of the flash memory I/F circuit provides read access and program access from the CPU to flash
memory. Programming to and erasing from flash memory are enabled by execution of an instruction from
the CPU via the flash memory I/F circuit. This allows reprogramming in the mounted state under CPU
control and improvement of programming data efficiency.
Selector operations such as enable sector protect are not available.
n Features of 1-Mbit Flash Memory
• 128 Kword × 8/64 Kword × 16 bit (16 K + 8 K + 8 K + 32 K + 64 K) sectors
• Uses automatic program algorithm (Embedded Algorithm
• Erase pause/restart function
• Detects completion of writing/erasing using data polling or toggle bit functions
• Detects completion of writing/erasing by CPU interrupts
• Programming/erase count (minimum): 10,000 times
• Compatible with JEDEC standard commands
• Sector erase function (any combination of sectors)
• Sector protection function
• Sector protection temporary cancel function
• Automatic sleep mode function
• The flash memory interface circuit makes it possible to determine whether to use control from the external
pins by the writer or to use control from the internal bus by the CPU when programming to and erasing
from flash memory.
TM
Embedded Algorithm
n Programming to and erasing from flash memory
Programming to and erasing from flash memory cannot be performed at one time. At programming to and
erasing from flash memory, copying programs temporarily in flash memory into RAM only permits
programming, without program access from flash memory.
n Flash memory register
Flash memory control status register (FMCS)
Bit No.
Address: 0000AE
H
Read/write →
Initial value →
1-MBIT FLASH MEMORY
is a registered trademark of Advanced Micro Devices, Inc.
7
6
INTE
WE
RDYINT
(R/W)
(R/W)
(R/W)
(0)
(0)
(0)
TM
: the same manner as MBM29F400TA)
5
4
3
RDY
Reserved
(R)
(W)
(1)
(0)
25-3
2
1
0
LPM1
LPM0
Reserved
(W)
(W)
(R/W)
(0)
(0)
(0)
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